[X86] Cast atomic vectors in IR to support floats

[jofrn]

This commit casts floats to ints in an atomic load during AtomicExpand to support
floating point types. It also is required to support 128 bit vectors in SSE/AVX.

[jofrn]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• [AtomicExpand] Add bitcasts when expanding load atomic vector #148900
• [X86] Cast atomic vectors in IR to support floats #148899 👈 (View in Graphite)
• [X86] Remove extra MOV after widening atomic load #148898
• [SelectionDAG] Widen <2 x T> vector types for atomic load #148897
• [X86] Add atomic vector tests for unaligned >1 sizes. #148896
• [X86] Manage atomic load of fp -> int promotion in DAG #148895
• [SelectionDAG] Legalize <1 x T> vector types for atomic load #148894
• IR/Verifier: Allow vector type in atomic load and store #148893
• main

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[llvmbot]

@llvm/pr-subscribers-backend-x86

Author: None (jofrn)

Changes

This commit casts floats to ints in an atomic load during AtomicExpand to support
floating point types. It also is required to support 128 bit vectors in SSE/AVX.

---

Full diff: https://github.com/llvm/llvm-project/pull/148899.diff

3 Files Affected:

• (modified) llvm/lib/Target/X86/X86ISelLowering.cpp (+7)
• (modified) llvm/lib/Target/X86/X86ISelLowering.h (+2)
• (modified) llvm/test/CodeGen/X86/atomic-load-store.ll (+163-18)

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 776d3c0a42e2f..3debf30da0a29 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -32070,6 +32070,13 @@ X86TargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *AI) const {
   }
 }
 
+TargetLowering::AtomicExpansionKind
+X86TargetLowering::shouldCastAtomicLoadInIR(LoadInst *LI) const {
+  if (LI->getType()->getScalarType()->isFloatingPointTy())
+    return AtomicExpansionKind::CastToInteger;
+  return AtomicExpansionKind::None;
+}
+
 LoadInst *
 X86TargetLowering::lowerIdempotentRMWIntoFencedLoad(AtomicRMWInst *AI) const {
   unsigned NativeWidth = Subtarget.is64Bit() ? 64 : 32;
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index 5cb6b3e493a32..43cddb2b53bd6 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -1839,6 +1839,8 @@ namespace llvm {
     shouldExpandAtomicRMWInIR(AtomicRMWInst *AI) const override;
     TargetLoweringBase::AtomicExpansionKind
     shouldExpandLogicAtomicRMWInIR(AtomicRMWInst *AI) const;
+    TargetLoweringBase::AtomicExpansionKind
+    shouldCastAtomicLoadInIR(LoadInst *LI) const override;
     void emitBitTestAtomicRMWIntrinsic(AtomicRMWInst *AI) const override;
     void emitCmpArithAtomicRMWIntrinsic(AtomicRMWInst *AI) const override;
 
diff --git a/llvm/test/CodeGen/X86/atomic-load-store.ll b/llvm/test/CodeGen/X86/atomic-load-store.ll
index 4b818b6cfa57e..039edcbf83544 100644
--- a/llvm/test/CodeGen/X86/atomic-load-store.ll
+++ b/llvm/test/CodeGen/X86/atomic-load-store.ll
@@ -207,19 +207,19 @@ define <1 x bfloat> @atomic_vec1_bfloat(ptr %x) {
 ; CHECK-O3-LABEL: atomic_vec1_bfloat:
 ; CHECK-O3:       # %bb.0:
 ; CHECK-O3-NEXT:    movzwl (%rdi), %eax
-; CHECK-O3-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-O3-NEXT:    movd %eax, %xmm0
 ; CHECK-O3-NEXT:    retq
 ;
 ; CHECK-SSE-O3-LABEL: atomic_vec1_bfloat:
 ; CHECK-SSE-O3:       # %bb.0:
 ; CHECK-SSE-O3-NEXT:    movzwl (%rdi), %eax
-; CHECK-SSE-O3-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-SSE-O3-NEXT:    movd %eax, %xmm0
 ; CHECK-SSE-O3-NEXT:    retq
 ;
 ; CHECK-AVX-O3-LABEL: atomic_vec1_bfloat:
 ; CHECK-AVX-O3:       # %bb.0:
 ; CHECK-AVX-O3-NEXT:    movzwl (%rdi), %eax
-; CHECK-AVX-O3-NEXT:    vpinsrw $0, %eax, %xmm0, %xmm0
+; CHECK-AVX-O3-NEXT:    vmovd %eax, %xmm0
 ; CHECK-AVX-O3-NEXT:    retq
 ;
 ; CHECK-O0-LABEL: atomic_vec1_bfloat:
@@ -227,8 +227,7 @@ define <1 x bfloat> @atomic_vec1_bfloat(ptr %x) {
 ; CHECK-O0-NEXT:    movw (%rdi), %cx
 ; CHECK-O0-NEXT:    # implicit-def: $eax
 ; CHECK-O0-NEXT:    movw %cx, %ax
-; CHECK-O0-NEXT:    # implicit-def: $xmm0
-; CHECK-O0-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-O0-NEXT:    movd %eax, %xmm0
 ; CHECK-O0-NEXT:    retq
 ;
 ; CHECK-SSE-O0-LABEL: atomic_vec1_bfloat:
@@ -236,8 +235,7 @@ define <1 x bfloat> @atomic_vec1_bfloat(ptr %x) {
 ; CHECK-SSE-O0-NEXT:    movw (%rdi), %cx
 ; CHECK-SSE-O0-NEXT:    # implicit-def: $eax
 ; CHECK-SSE-O0-NEXT:    movw %cx, %ax
-; CHECK-SSE-O0-NEXT:    # implicit-def: $xmm0
-; CHECK-SSE-O0-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-SSE-O0-NEXT:    movd %eax, %xmm0
 ; CHECK-SSE-O0-NEXT:    retq
 ;
 ; CHECK-AVX-O0-LABEL: atomic_vec1_bfloat:
@@ -245,8 +243,7 @@ define <1 x bfloat> @atomic_vec1_bfloat(ptr %x) {
 ; CHECK-AVX-O0-NEXT:    movw (%rdi), %cx
 ; CHECK-AVX-O0-NEXT:    # implicit-def: $eax
 ; CHECK-AVX-O0-NEXT:    movw %cx, %ax
-; CHECK-AVX-O0-NEXT:    # implicit-def: $xmm0
-; CHECK-AVX-O0-NEXT:    vpinsrw $0, %eax, %xmm0, %xmm0
+; CHECK-AVX-O0-NEXT:    vmovd %eax, %xmm0
 ; CHECK-AVX-O0-NEXT:    retq
   %ret = load atomic <1 x bfloat>, ptr %x acquire, align 2
   ret <1 x bfloat> %ret
@@ -377,6 +374,74 @@ define <2 x float> @atomic_vec2_float_align(ptr %x) {
   ret <2 x float> %ret
 }
 
+define <2 x half> @atomic_vec2_half(ptr %x) {
+; CHECK-O3-LABEL: atomic_vec2_half:
+; CHECK-O3:       # %bb.0:
+; CHECK-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-O3-NEXT:    retq
+;
+; CHECK-SSE-O3-LABEL: atomic_vec2_half:
+; CHECK-SSE-O3:       # %bb.0:
+; CHECK-SSE-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-SSE-O3-NEXT:    retq
+;
+; CHECK-AVX-O3-LABEL: atomic_vec2_half:
+; CHECK-AVX-O3:       # %bb.0:
+; CHECK-AVX-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-AVX-O3-NEXT:    retq
+;
+; CHECK-O0-LABEL: atomic_vec2_half:
+; CHECK-O0:       # %bb.0:
+; CHECK-O0-NEXT:    movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-O0-NEXT:    retq
+;
+; CHECK-SSE-O0-LABEL: atomic_vec2_half:
+; CHECK-SSE-O0:       # %bb.0:
+; CHECK-SSE-O0-NEXT:    movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-SSE-O0-NEXT:    retq
+;
+; CHECK-AVX-O0-LABEL: atomic_vec2_half:
+; CHECK-AVX-O0:       # %bb.0:
+; CHECK-AVX-O0-NEXT:    movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-AVX-O0-NEXT:    retq
+  %ret = load atomic <2 x half>, ptr %x acquire, align 4
+  ret <2 x half> %ret
+}
+
+define <2 x bfloat> @atomic_vec2_bfloat(ptr %x) {
+; CHECK-O3-LABEL: atomic_vec2_bfloat:
+; CHECK-O3:       # %bb.0:
+; CHECK-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-O3-NEXT:    retq
+;
+; CHECK-SSE-O3-LABEL: atomic_vec2_bfloat:
+; CHECK-SSE-O3:       # %bb.0:
+; CHECK-SSE-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-SSE-O3-NEXT:    retq
+;
+; CHECK-AVX-O3-LABEL: atomic_vec2_bfloat:
+; CHECK-AVX-O3:       # %bb.0:
+; CHECK-AVX-O3-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-AVX-O3-NEXT:    retq
+;
+; CHECK-O0-LABEL: atomic_vec2_bfloat:
+; CHECK-O0:       # %bb.0:
+; CHECK-O0-NEXT:    movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-O0-NEXT:    retq
+;
+; CHECK-SSE-O0-LABEL: atomic_vec2_bfloat:
+; CHECK-SSE-O0:       # %bb.0:
+; CHECK-SSE-O0-NEXT:    movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-SSE-O0-NEXT:    retq
+;
+; CHECK-AVX-O0-LABEL: atomic_vec2_bfloat:
+; CHECK-AVX-O0:       # %bb.0:
+; CHECK-AVX-O0-NEXT:    movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
+; CHECK-AVX-O0-NEXT:    retq
+  %ret = load atomic <2 x bfloat>, ptr %x acquire, align 4
+  ret <2 x bfloat> %ret
+}
+
 define <1 x ptr> @atomic_vec1_ptr(ptr %x) nounwind {
 ; CHECK-O3-LABEL: atomic_vec1_ptr:
 ; CHECK-O3:       # %bb.0:
@@ -457,19 +522,19 @@ define <1 x half> @atomic_vec1_half(ptr %x) {
 ; CHECK-O3-LABEL: atomic_vec1_half:
 ; CHECK-O3:       # %bb.0:
 ; CHECK-O3-NEXT:    movzwl (%rdi), %eax
-; CHECK-O3-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-O3-NEXT:    movd %eax, %xmm0
 ; CHECK-O3-NEXT:    retq
 ;
 ; CHECK-SSE-O3-LABEL: atomic_vec1_half:
 ; CHECK-SSE-O3:       # %bb.0:
 ; CHECK-SSE-O3-NEXT:    movzwl (%rdi), %eax
-; CHECK-SSE-O3-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-SSE-O3-NEXT:    movd %eax, %xmm0
 ; CHECK-SSE-O3-NEXT:    retq
 ;
 ; CHECK-AVX-O3-LABEL: atomic_vec1_half:
 ; CHECK-AVX-O3:       # %bb.0:
 ; CHECK-AVX-O3-NEXT:    movzwl (%rdi), %eax
-; CHECK-AVX-O3-NEXT:    vpinsrw $0, %eax, %xmm0, %xmm0
+; CHECK-AVX-O3-NEXT:    vmovd %eax, %xmm0
 ; CHECK-AVX-O3-NEXT:    retq
 ;
 ; CHECK-O0-LABEL: atomic_vec1_half:
@@ -477,8 +542,7 @@ define <1 x half> @atomic_vec1_half(ptr %x) {
 ; CHECK-O0-NEXT:    movw (%rdi), %cx
 ; CHECK-O0-NEXT:    # implicit-def: $eax
 ; CHECK-O0-NEXT:    movw %cx, %ax
-; CHECK-O0-NEXT:    # implicit-def: $xmm0
-; CHECK-O0-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-O0-NEXT:    movd %eax, %xmm0
 ; CHECK-O0-NEXT:    retq
 ;
 ; CHECK-SSE-O0-LABEL: atomic_vec1_half:
@@ -486,8 +550,7 @@ define <1 x half> @atomic_vec1_half(ptr %x) {
 ; CHECK-SSE-O0-NEXT:    movw (%rdi), %cx
 ; CHECK-SSE-O0-NEXT:    # implicit-def: $eax
 ; CHECK-SSE-O0-NEXT:    movw %cx, %ax
-; CHECK-SSE-O0-NEXT:    # implicit-def: $xmm0
-; CHECK-SSE-O0-NEXT:    pinsrw $0, %eax, %xmm0
+; CHECK-SSE-O0-NEXT:    movd %eax, %xmm0
 ; CHECK-SSE-O0-NEXT:    retq
 ;
 ; CHECK-AVX-O0-LABEL: atomic_vec1_half:
@@ -495,8 +558,7 @@ define <1 x half> @atomic_vec1_half(ptr %x) {
 ; CHECK-AVX-O0-NEXT:    movw (%rdi), %cx
 ; CHECK-AVX-O0-NEXT:    # implicit-def: $eax
 ; CHECK-AVX-O0-NEXT:    movw %cx, %ax
-; CHECK-AVX-O0-NEXT:    # implicit-def: $xmm0
-; CHECK-AVX-O0-NEXT:    vpinsrw $0, %eax, %xmm0, %xmm0
+; CHECK-AVX-O0-NEXT:    vmovd %eax, %xmm0
 ; CHECK-AVX-O0-NEXT:    retq
   %ret = load atomic <1 x half>, ptr %x acquire, align 2
   ret <1 x half> %ret
@@ -841,6 +903,89 @@ define <4 x i16> @atomic_vec4_i16(ptr %x) nounwind {
   ret <4 x i16> %ret
 }
 
+define <4 x half> @atomic_vec4_half(ptr %x) nounwind {
+; CHECK-LABEL: atomic_vec4_half:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movq (%rdi), %xmm0
+; CHECK-NEXT:    retq
+  %ret = load atomic <4 x half>, ptr %x acquire, align 8
+  ret <4 x half> %ret
+}
+
+define <4 x bfloat> @atomic_vec4_bfloat(ptr %x) nounwind {
+; CHECK-LABEL: atomic_vec4_bfloat:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movq (%rdi), %xmm0
+; CHECK-NEXT:    retq
+  %ret = load atomic <4 x bfloat>, ptr %x acquire, align 8
+  ret <4 x bfloat> %ret
+}
+
+define <4 x float> @atomic_vec4_float_align(ptr %x) nounwind {
+; CHECK-O3-LABEL: atomic_vec4_float_align:
+; CHECK-O3:       # %bb.0:
+; CHECK-O3-NEXT:    pushq %rax
+; CHECK-O3-NEXT:    movl $2, %esi
+; CHECK-O3-NEXT:    callq __atomic_load_16@PLT
+; CHECK-O3-NEXT:    movq %rdx, %xmm1
+; CHECK-O3-NEXT:    movq %rax, %xmm0
+; CHECK-O3-NEXT:    punpcklqdq {{.*#+}} xmm0 = xmm0[0],xmm1[0]
+; CHECK-O3-NEXT:    popq %rax
+; CHECK-O3-NEXT:    retq
+;
+; CHECK-SSE-O3-LABEL: atomic_vec4_float_align:
+; CHECK-SSE-O3:       # %bb.0:
+; CHECK-SSE-O3-NEXT:    pushq %rbx
+; CHECK-SSE-O3-NEXT:    xorl %eax, %eax
+; CHECK-SSE-O3-NEXT:    xorl %edx, %edx
+; CHECK-SSE-O3-NEXT:    xorl %ecx, %ecx
+; CHECK-SSE-O3-NEXT:    xorl %ebx, %ebx
+; CHECK-SSE-O3-NEXT:    lock cmpxchg16b (%rdi)
+; CHECK-SSE-O3-NEXT:    movq %rdx, %xmm1
+; CHECK-SSE-O3-NEXT:    movq %rax, %xmm0
+; CHECK-SSE-O3-NEXT:    punpcklqdq {{.*#+}} xmm0 = xmm0[0],xmm1[0]
+; CHECK-SSE-O3-NEXT:    popq %rbx
+; CHECK-SSE-O3-NEXT:    retq
+;
+; CHECK-AVX-O3-LABEL: atomic_vec4_float_align:
+; CHECK-AVX-O3:       # %bb.0:
+; CHECK-AVX-O3-NEXT:    vmovaps (%rdi), %xmm0
+; CHECK-AVX-O3-NEXT:    retq
+;
+; CHECK-O0-LABEL: atomic_vec4_float_align:
+; CHECK-O0:       # %bb.0:
+; CHECK-O0-NEXT:    pushq %rax
+; CHECK-O0-NEXT:    movl $2, %esi
+; CHECK-O0-NEXT:    callq __atomic_load_16@PLT
+; CHECK-O0-NEXT:    movq %rdx, %xmm1
+; CHECK-O0-NEXT:    movq %rax, %xmm0
+; CHECK-O0-NEXT:    punpcklqdq {{.*#+}} xmm0 = xmm0[0],xmm1[0]
+; CHECK-O0-NEXT:    popq %rax
+; CHECK-O0-NEXT:    retq
+;
+; CHECK-SSE-O0-LABEL: atomic_vec4_float_align:
+; CHECK-SSE-O0:       # %bb.0:
+; CHECK-SSE-O0-NEXT:    pushq %rbx
+; CHECK-SSE-O0-NEXT:    xorl %eax, %eax
+; CHECK-SSE-O0-NEXT:    movl %eax, %ebx
+; CHECK-SSE-O0-NEXT:    movq %rbx, %rax
+; CHECK-SSE-O0-NEXT:    movq %rbx, %rdx
+; CHECK-SSE-O0-NEXT:    movq %rbx, %rcx
+; CHECK-SSE-O0-NEXT:    lock cmpxchg16b (%rdi)
+; CHECK-SSE-O0-NEXT:    movq %rdx, %xmm1
+; CHECK-SSE-O0-NEXT:    movq %rax, %xmm0
+; CHECK-SSE-O0-NEXT:    punpcklqdq {{.*#+}} xmm0 = xmm0[0],xmm1[0]
+; CHECK-SSE-O0-NEXT:    popq %rbx
+; CHECK-SSE-O0-NEXT:    retq
+;
+; CHECK-AVX-O0-LABEL: atomic_vec4_float_align:
+; CHECK-AVX-O0:       # %bb.0:
+; CHECK-AVX-O0-NEXT:    vmovaps (%rdi), %xmm0
+; CHECK-AVX-O0-NEXT:    retq
+  %ret = load atomic <4 x float>, ptr %x acquire, align 16
+  ret <4 x float> %ret
+}
+
 define <4 x float> @atomic_vec4_float(ptr %x) nounwind {
 ; CHECK-O3-LABEL: atomic_vec4_float:
 ; CHECK-O3:       # %bb.0: