[X86][GlobalISel] Added support for SQRT function

[JaydeepChauhan14]

No description provided.

[llvmbot]

@llvm/pr-subscribers-llvm-globalisel

@llvm/pr-subscribers-backend-x86

Author: None (JaydeepChauhan14)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/132356.diff

4 Files Affected:

• (modified) llvm/lib/Target/X86/GISel/X86LegalizerInfo.cpp (+5)
• (modified) llvm/lib/Target/X86/GISel/X86RegisterBankInfo.cpp (+1)
• (added) llvm/test/CodeGen/X86/GlobalISel/sqrt.mir (+68)
• (modified) llvm/test/CodeGen/X86/isel-sqrt.ll (+10-9)

diff --git a/llvm/lib/Target/X86/GISel/X86LegalizerInfo.cpp b/llvm/lib/Target/X86/GISel/X86LegalizerInfo.cpp
index 24bf0dd378641..b474d6a3f6356 100644
--- a/llvm/lib/Target/X86/GISel/X86LegalizerInfo.cpp
+++ b/llvm/lib/Target/X86/GISel/X86LegalizerInfo.cpp
@@ -105,6 +105,11 @@ X86LegalizerInfo::X86LegalizerInfo(const X86Subtarget &STI,
                                G_FEXP10, G_FLOG, G_FLOG2, G_FLOG10})
       .libcall();
 
+  getActionDefinitionsBuilder(G_FSQRT)
+      .legalFor(HasSSE1 || UseX87, {s32})
+      .legalFor(HasSSE2 || UseX87, {s64})
+      .legalFor(UseX87, {s80});
+
   // merge/unmerge
   for (unsigned Op : {G_MERGE_VALUES, G_UNMERGE_VALUES}) {
     unsigned BigTyIdx = Op == G_MERGE_VALUES ? 0 : 1;
diff --git a/llvm/lib/Target/X86/GISel/X86RegisterBankInfo.cpp b/llvm/lib/Target/X86/GISel/X86RegisterBankInfo.cpp
index 42faf4299c6d5..0baca81494694 100644
--- a/llvm/lib/Target/X86/GISel/X86RegisterBankInfo.cpp
+++ b/llvm/lib/Target/X86/GISel/X86RegisterBankInfo.cpp
@@ -288,6 +288,7 @@ X86RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
   SmallVector<PartialMappingIdx, 4> OpRegBankIdx(NumOperands);
 
   switch (Opc) {
+  case TargetOpcode::G_FSQRT:
   case TargetOpcode::G_FPEXT:
   case TargetOpcode::G_FPTRUNC:
   case TargetOpcode::G_FCONSTANT:
diff --git a/llvm/test/CodeGen/X86/GlobalISel/sqrt.mir b/llvm/test/CodeGen/X86/GlobalISel/sqrt.mir
new file mode 100644
index 0000000000000..b55a9f8dceca0
--- /dev/null
+++ b/llvm/test/CodeGen/X86/GlobalISel/sqrt.mir
@@ -0,0 +1,68 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=i686-linux-gnu -run-pass=regbankselect,instruction-select -disable-gisel-legality-check -global-isel -verify-machineinstrs %s -o - | FileCheck %s --check-prefixes GISEL-I686
+
+---
+name:            test_sqrt_f32
+alignment:       16
+legalized:       true
+fixedStack:
+  - { id: 0, type: default, offset: 0, size: 4, alignment: 16, stack-id: default,
+      isImmutable: true, isAliased: false, callee-saved-register: '', callee-saved-restored: true,
+      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
+body:             |
+  bb.1:
+    ; GISEL-I686-LABEL: name: test_sqrt_f32
+    ; GISEL-I686: [[LD_Fp32m:%[0-9]+]]:rfp32 = LD_Fp32m %fixed-stack.0, 1, $noreg, 0, $noreg, implicit-def $fpsw, implicit $fpcw :: (invariant load (s32) from %fixed-stack.0, align 16)
+    ; GISEL-I686-NEXT: [[SQRT_Fp32_:%[0-9]+]]:rfp32 = nofpexcept SQRT_Fp32 [[LD_Fp32m]], implicit-def dead $fpsw, implicit $fpcw
+    ; GISEL-I686-NEXT: $fp0 = COPY [[SQRT_Fp32_]]
+    ; GISEL-I686-NEXT: RET 0, implicit $fp0
+    %1:_(p0) = G_FRAME_INDEX %fixed-stack.0
+    %0:_(s32) = G_LOAD %1(p0) :: (invariant load (s32) from %fixed-stack.0, align 16)
+    %2:_(s32) = G_FSQRT %0
+    $fp0 = COPY %2(s32)
+    RET 0, implicit $fp0
+
+...
+---
+name:            test_sqrt_f64
+alignment:       16
+legalized:       true
+fixedStack:
+  - { id: 0, type: default, offset: 0, size: 8, alignment: 16, stack-id: default,
+      isImmutable: true, isAliased: false, callee-saved-register: '', callee-saved-restored: true,
+      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
+body:             |
+  bb.1:
+    ; GISEL-I686-LABEL: name: test_sqrt_f64
+    ; GISEL-I686: [[DEF:%[0-9]+]]:rfp64 = IMPLICIT_DEF
+    ; GISEL-I686-NEXT: [[SQRT_Fp64_:%[0-9]+]]:rfp64 = nofpexcept SQRT_Fp64 [[DEF]], implicit-def dead $fpsw, implicit $fpcw
+    ; GISEL-I686-NEXT: $fp0 = COPY [[SQRT_Fp64_]]
+    ; GISEL-I686-NEXT: RET 0, implicit $fp0
+    %0:_(s64) = IMPLICIT_DEF
+    %2:_(s64) = G_FSQRT %0
+    $fp0 = COPY %2(s64)
+    RET 0, implicit $fp0
+
+...
+---
+name:            test_sqrt_f80
+alignment:       16
+legalized:       true
+fixedStack:
+  - { id: 0, type: default, offset: 0, size: 10, alignment: 16, stack-id: default,
+      isImmutable: true, isAliased: false, callee-saved-register: '', callee-saved-restored: true,
+      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
+body:             |
+  bb.1:
+    ; GISEL-I686-LABEL: name: test_sqrt_f80
+    ; GISEL-I686: [[LD_Fp80m:%[0-9]+]]:rfp80 = LD_Fp80m %fixed-stack.0, 1, $noreg, 0, $noreg, implicit-def $fpsw, implicit $fpcw :: (invariant load (s80) from %fixed-stack.0, align 16)
+    ; GISEL-I686-NEXT: [[SQRT_Fp80_:%[0-9]+]]:rfp80 = nofpexcept SQRT_Fp80 [[LD_Fp80m]], implicit-def dead $fpsw, implicit $fpcw
+    ; GISEL-I686-NEXT: $fp0 = COPY [[SQRT_Fp80_]]
+    ; GISEL-I686-NEXT: RET 0, implicit $fp0
+    %1:_(p0) = G_FRAME_INDEX %fixed-stack.0
+    %0:_(s80) = G_LOAD %1(p0) :: (invariant load (s80) from %fixed-stack.0, align 16)
+    %2:_(s80) = G_FSQRT %0
+    $fp0 = COPY %2(s80)
+    RET 0, implicit $fp0
+
+...
diff --git a/llvm/test/CodeGen/X86/isel-sqrt.ll b/llvm/test/CodeGen/X86/isel-sqrt.ll
index 9ac68a11d748c..7204e37347618 100644
--- a/llvm/test/CodeGen/X86/isel-sqrt.ll
+++ b/llvm/test/CodeGen/X86/isel-sqrt.ll
@@ -1,13 +1,14 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2                       | FileCheck %s --check-prefixes=X64,SSE2
-; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2 -fast-isel            | FileCheck %s --check-prefixes=X64,SSE2
-; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2 -global-isel -global-isel-abort=2 | FileCheck %s --check-prefixes=X64,SSE2
-; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx                       | FileCheck %s --check-prefixes=X64,AVX
-; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx -fast-isel            | FileCheck %s --check-prefixes=X64,AVX
-; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx -global-isel -global-isel-abort=2 | FileCheck %s --check-prefixes=X64,AVX
-; RUN: llc < %s -mtriple=i686-linux-gnu -global-isel=0 -fast-isel=0                  | FileCheck %s --check-prefixes=X86,SDAG-X86
-; RUN: llc < %s -mtriple=i686-linux-gnu -fast-isel                                   | FileCheck %s --check-prefixes=X86,FASTISEL-X86
-; RUN: llc < %s -mtriple=i686-linux-gnu -global-isel -global-isel-abort=2            | FileCheck %s --check-prefixes=X86,GISEL-X86
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2                 | FileCheck %s --check-prefixes=X64,SSE2
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2 -fast-isel      | FileCheck %s --check-prefixes=X64,SSE2
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2 -global-isel    | FileCheck %s --check-prefixes=X64,SSE2
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx                 | FileCheck %s --check-prefixes=X64,AVX
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx -fast-isel      | FileCheck %s --check-prefixes=X64,AVX
+; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx -global-isel    | FileCheck %s --check-prefixes=X64,AVX
+; RUN: llc < %s -mtriple=i686-linux-gnu -global-isel=0 -fast-isel=0            | FileCheck %s --check-prefixes=X86,SDAG-X86
+; RUN: llc < %s -mtriple=i686-linux-gnu -fast-isel                             | FileCheck %s --check-prefixes=X86,FASTISEL-X86
+; TODO: The last RUN line will fails GISEL selection and will fallback to DAG selection due to lack of support for loads/stores in i686 mode, support is expected soon enough, for this reason the llvm/test/CodeGen/X86/GlobalISel/sqrt.mir test is added for now because of the lack of support for i686 in GlobalISel.
+; RUN: llc < %s -mtriple=i686-linux-gnu -global-isel -global-isel-abort=2      | FileCheck %s --check-prefixes=X86,GISEL-X86
 
 define float @test_sqrt_f32(float %a) {
 ; SSE2-LABEL: test_sqrt_f32:

[JaydeepChauhan14]

@arsenm, @RKSimon, @e-kud please review PR.

[e-kud]

-global-isel-abort=1 is required otherwise we don't know whether we test GlobalISel or not.

[JaydeepChauhan14]

Done

[e-kud]

LGTM

[RKSimon]

LGTM