[llvm] [NVPTX] Consistently check fast-math flags when lowering fsqrt (PR #143776)

via llvm-commits llvm-commits at lists.llvm.org
Wed Jun 11 12:52:10 PDT 2025


llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-nvptx

Author: Alex MacLean (AlexMaclean)

<details>
<summary>Changes</summary>

Ensure that we check the global, function-level, and instruction-level flags when considering whether to use `sqrt.rn` or `sqrt.approx` to lower either `@<!-- -->llvm.sqrt.f32` or `@<!-- -->llvm.nvvm.sqrt.f`

---

Patch is 46.55 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/143776.diff


8 Files Affected:

- (modified) llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp (+2-2) 
- (modified) llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.h (+1-1) 
- (modified) llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp (+17-7) 
- (modified) llvm/lib/Target/NVPTX/NVPTXISelLowering.h (+2-1) 
- (modified) llvm/lib/Target/NVPTX/NVPTXInstrInfo.td (-3) 
- (modified) llvm/lib/Target/NVPTX/NVPTXIntrinsics.td (+16-19) 
- (modified) llvm/test/CodeGen/NVPTX/fast-math.ll (+372-95) 
- (modified) llvm/test/CodeGen/NVPTX/sqrt-approx.ll (+285-54) 


``````````diff
diff --git a/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp b/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp
index 32223bf3d601e..121ffc5b9d805 100644
--- a/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp
@@ -71,8 +71,8 @@ NVPTXDAGToDAGISel::getDivF32Level(const SDNode *N) const {
   return Subtarget->getTargetLowering()->getDivF32Level(*MF, *N);
 }
 
-bool NVPTXDAGToDAGISel::usePrecSqrtF32() const {
-  return Subtarget->getTargetLowering()->usePrecSqrtF32();
+bool NVPTXDAGToDAGISel::usePrecSqrtF32(const SDNode *N) const {
+  return Subtarget->getTargetLowering()->usePrecSqrtF32(*MF, N);
 }
 
 bool NVPTXDAGToDAGISel::useF32FTZ() const {
diff --git a/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.h b/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.h
index 71a5b7ff8cd30..473f4781a6c38 100644
--- a/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.h
+++ b/llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.h
@@ -44,7 +44,7 @@ class LLVM_LIBRARY_VISIBILITY NVPTXDAGToDAGISel : public SelectionDAGISel {
   bool doMulWide;
 
   NVPTX::DivPrecisionLevel getDivF32Level(const SDNode *N) const;
-  bool usePrecSqrtF32() const;
+  bool usePrecSqrtF32(const SDNode *N) const;
   bool useF32FTZ() const;
   bool allowFMA() const;
   bool allowUnsafeFPMath() const;
diff --git a/llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp b/llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp
index d6a134d9abafd..492f4ab76fdbb 100644
--- a/llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp
@@ -134,14 +134,23 @@ NVPTXTargetLowering::getDivF32Level(const MachineFunction &MF,
   return NVPTX::DivPrecisionLevel::IEEE754;
 }
 
-bool NVPTXTargetLowering::usePrecSqrtF32() const {
-  if (UsePrecSqrtF32.getNumOccurrences() > 0) {
-    // If nvptx-prec-sqrtf32 is used on the command-line, always honor it
+bool NVPTXTargetLowering::usePrecSqrtF32(const MachineFunction &MF,
+                                         const SDNode *N) const {
+  // If nvptx-prec-sqrtf32 is used on the command-line, always honor it
+  if (UsePrecSqrtF32.getNumOccurrences() > 0)
     return UsePrecSqrtF32;
-  } else {
-    // Otherwise, use sqrt.approx if fast math is enabled
-    return !getTargetMachine().Options.UnsafeFPMath;
+
+  // Otherwise, use sqrt.approx if fast math is enabled
+  if (allowUnsafeFPMath(MF))
+    return false;
+
+  if (N) {
+    const SDNodeFlags Flags = N->getFlags();
+    if (Flags.hasApproximateFuncs())
+      return false;
   }
+
+  return true;
 }
 
 bool NVPTXTargetLowering::useF32FTZ(const MachineFunction &MF) const {
@@ -1134,7 +1143,8 @@ SDValue NVPTXTargetLowering::getSqrtEstimate(SDValue Operand, SelectionDAG &DAG,
                                              bool &UseOneConst,
                                              bool Reciprocal) const {
   if (!(Enabled == ReciprocalEstimate::Enabled ||
-        (Enabled == ReciprocalEstimate::Unspecified && !usePrecSqrtF32())))
+        (Enabled == ReciprocalEstimate::Unspecified &&
+         !usePrecSqrtF32(DAG.getMachineFunction()))))
     return SDValue();
 
   if (ExtraSteps == ReciprocalEstimate::Unspecified)
diff --git a/llvm/lib/Target/NVPTX/NVPTXISelLowering.h b/llvm/lib/Target/NVPTX/NVPTXISelLowering.h
index 8d71022a1f102..0a54a8fd71f32 100644
--- a/llvm/lib/Target/NVPTX/NVPTXISelLowering.h
+++ b/llvm/lib/Target/NVPTX/NVPTXISelLowering.h
@@ -225,7 +225,8 @@ class NVPTXTargetLowering : public TargetLowering {
 
   // Get whether we should use a precise or approximate 32-bit floating point
   // sqrt instruction.
-  bool usePrecSqrtF32() const;
+  bool usePrecSqrtF32(const MachineFunction &MF,
+                      const SDNode *N = nullptr) const;
 
   // Get whether we should use instructions that flush floating-point denormals
   // to sign-preserving zero.
diff --git a/llvm/lib/Target/NVPTX/NVPTXInstrInfo.td b/llvm/lib/Target/NVPTX/NVPTXInstrInfo.td
index b646d39194c7e..ecaca4a011053 100644
--- a/llvm/lib/Target/NVPTX/NVPTXInstrInfo.td
+++ b/llvm/lib/Target/NVPTX/NVPTXInstrInfo.td
@@ -151,9 +151,6 @@ def doRsqrtOpt : Predicate<"doRsqrtOpt()">;
 
 def doMulWide      : Predicate<"doMulWide">;
 
-def do_SQRTF32_APPROX : Predicate<"!usePrecSqrtF32()">;
-def do_SQRTF32_RN : Predicate<"usePrecSqrtF32()">;
-
 def hasHWROT32 : Predicate<"Subtarget->hasHWROT32()">;
 def noHWROT32 : Predicate<"!Subtarget->hasHWROT32()">;
 def hasDotInstructions : Predicate<"Subtarget->hasDotInstructions()">;
diff --git a/llvm/lib/Target/NVPTX/NVPTXIntrinsics.td b/llvm/lib/Target/NVPTX/NVPTXIntrinsics.td
index f918160001ba5..1c38cf0cac0ee 100644
--- a/llvm/lib/Target/NVPTX/NVPTXIntrinsics.td
+++ b/llvm/lib/Target/NVPTX/NVPTXIntrinsics.td
@@ -1525,15 +1525,18 @@ def INT_NVVM_SQRT_RZ_D : F_MATH_1<"sqrt.rz.f64", F64RT, F64RT, int_nvvm_sqrt_rz_
 def INT_NVVM_SQRT_RM_D : F_MATH_1<"sqrt.rm.f64", F64RT, F64RT, int_nvvm_sqrt_rm_d>;
 def INT_NVVM_SQRT_RP_D : F_MATH_1<"sqrt.rp.f64", F64RT, F64RT, int_nvvm_sqrt_rp_d>;
 
+def fsqrt_approx : PatFrags<(ops node:$a),
+                            [(fsqrt node:$a),
+                             (int_nvvm_sqrt_f node:$a)], [{
+  return !usePrecSqrtF32(N);
+}]>;
+
 // nvvm_sqrt intrinsic
-def : Pat<(int_nvvm_sqrt_f f32:$a),
-          (INT_NVVM_SQRT_RN_FTZ_F $a)>, Requires<[doF32FTZ, do_SQRTF32_RN]>;
-def : Pat<(int_nvvm_sqrt_f f32:$a),
-          (INT_NVVM_SQRT_RN_F $a)>, Requires<[do_SQRTF32_RN]>;
-def : Pat<(int_nvvm_sqrt_f f32:$a),
-          (INT_NVVM_SQRT_APPROX_FTZ_F $a)>, Requires<[doF32FTZ]>;
-def : Pat<(int_nvvm_sqrt_f f32:$a),
-          (INT_NVVM_SQRT_APPROX_F $a)>;
+def : Pat<(int_nvvm_sqrt_f f32:$a), (INT_NVVM_SQRT_RN_FTZ_F $a)>, Requires<[doF32FTZ]>;
+def : Pat<(int_nvvm_sqrt_f f32:$a), (INT_NVVM_SQRT_RN_F $a)>;
+
+def : Pat<(fsqrt_approx f32:$a), (INT_NVVM_SQRT_APPROX_FTZ_F $a)>, Requires<[doF32FTZ]>;
+def : Pat<(fsqrt_approx f32:$a), (INT_NVVM_SQRT_APPROX_F $a)>;
 
 //
 // Rsqrt
@@ -1556,20 +1559,14 @@ def: Pat<(fdiv f32imm_1, (int_nvvm_sqrt_approx_f f32:$a)),
 def: Pat<(fdiv f32imm_1, (int_nvvm_sqrt_approx_ftz_f f32:$a)),
          (INT_NVVM_RSQRT_APPROX_FTZ_F $a)>,
          Requires<[doRsqrtOpt]>;
-// same for int_nvvm_sqrt_f when non-precision sqrt is requested
-def: Pat<(fdiv f32imm_1, (int_nvvm_sqrt_f f32:$a)),
-         (INT_NVVM_RSQRT_APPROX_F $a)>,
-         Requires<[doRsqrtOpt, do_SQRTF32_APPROX, doNoF32FTZ]>;
-def: Pat<(fdiv f32imm_1, (int_nvvm_sqrt_f f32:$a)),
-         (INT_NVVM_RSQRT_APPROX_FTZ_F $a)>,
-         Requires<[doRsqrtOpt, do_SQRTF32_APPROX, doF32FTZ]>;
 
-def: Pat<(fdiv f32imm_1, (fsqrt f32:$a)),
+// same for int_nvvm_sqrt_f when non-precision sqrt is requested
+def: Pat<(fdiv f32imm_1, (fsqrt_approx f32:$a)),
          (INT_NVVM_RSQRT_APPROX_F $a)>,
-         Requires<[doRsqrtOpt, do_SQRTF32_APPROX, doNoF32FTZ]>;
-def: Pat<(fdiv f32imm_1, (fsqrt f32:$a)),
+         Requires<[doRsqrtOpt, doNoF32FTZ]>;
+def: Pat<(fdiv f32imm_1, (fsqrt_approx f32:$a)),
          (INT_NVVM_RSQRT_APPROX_FTZ_F $a)>,
-         Requires<[doRsqrtOpt, do_SQRTF32_APPROX, doF32FTZ]>;
+         Requires<[doRsqrtOpt, doF32FTZ]>;
 //
 // Add
 //
diff --git a/llvm/test/CodeGen/NVPTX/fast-math.ll b/llvm/test/CodeGen/NVPTX/fast-math.ll
index 4cb6a35e796fb..bc48d242f88fd 100644
--- a/llvm/test/CodeGen/NVPTX/fast-math.ll
+++ b/llvm/test/CodeGen/NVPTX/fast-math.ll
@@ -1,58 +1,114 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc < %s -mtriple=nvptx64 -mcpu=sm_20 | FileCheck %s
 ; RUN: %if ptxas %{ llc < %s -mtriple=nvptx64 -mcpu=sm_20 | %ptxas-verify %}
 
 declare float @llvm.sqrt.f32(float)
 declare double @llvm.sqrt.f64(double)
 
-; CHECK-LABEL: sqrt_div(
-; CHECK: sqrt.rn.f32
-; CHECK: div.rn.f32
 define float @sqrt_div(float %a, float %b) {
+; CHECK-LABEL: sqrt_div(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<5>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [sqrt_div_param_0];
+; CHECK-NEXT:    sqrt.rn.f32 %r2, %r1;
+; CHECK-NEXT:    ld.param.b32 %r3, [sqrt_div_param_1];
+; CHECK-NEXT:    div.rn.f32 %r4, %r2, %r3;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r4;
+; CHECK-NEXT:    ret;
   %t1 = tail call float @llvm.sqrt.f32(float %a)
   %t2 = fdiv float %t1, %b
   ret float %t2
 }
 
-; CHECK-LABEL: sqrt_div_fast(
-; CHECK: sqrt.rn.f32
-; CHECK: div.approx.f32
 define float @sqrt_div_fast(float %a, float %b) #0 {
+; CHECK-LABEL: sqrt_div_fast(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<5>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [sqrt_div_fast_param_0];
+; CHECK-NEXT:    sqrt.approx.f32 %r2, %r1;
+; CHECK-NEXT:    ld.param.b32 %r3, [sqrt_div_fast_param_1];
+; CHECK-NEXT:    div.approx.f32 %r4, %r2, %r3;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r4;
+; CHECK-NEXT:    ret;
   %t1 = tail call float @llvm.sqrt.f32(float %a)
   %t2 = fdiv float %t1, %b
   ret float %t2
 }
 
-; CHECK-LABEL: sqrt_div_fast_ninf(
-; CHECK: sqrt.approx.f32
-; CHECK: div.approx.f32
 define float @sqrt_div_fast_ninf(float %a, float %b) #0 {
+; CHECK-LABEL: sqrt_div_fast_ninf(
+; CHECK:       {
+; CHECK-NEXT:    .reg .pred %p<2>;
+; CHECK-NEXT:    .reg .b32 %r<7>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [sqrt_div_fast_ninf_param_0];
+; CHECK-NEXT:    sqrt.approx.f32 %r2, %r1;
+; CHECK-NEXT:    abs.f32 %r3, %r1;
+; CHECK-NEXT:    setp.lt.f32 %p1, %r3, 0f00800000;
+; CHECK-NEXT:    selp.f32 %r4, 0f00000000, %r2, %p1;
+; CHECK-NEXT:    ld.param.b32 %r5, [sqrt_div_fast_ninf_param_1];
+; CHECK-NEXT:    div.approx.f32 %r6, %r4, %r5;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r6;
+; CHECK-NEXT:    ret;
   %t1 = tail call ninf afn float @llvm.sqrt.f32(float %a)
   %t2 = fdiv float %t1, %b
   ret float %t2
 }
 
-; CHECK-LABEL: sqrt_div_ftz(
-; CHECK: sqrt.rn.ftz.f32
-; CHECK: div.rn.ftz.f32
 define float @sqrt_div_ftz(float %a, float %b) #1 {
+; CHECK-LABEL: sqrt_div_ftz(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<5>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [sqrt_div_ftz_param_0];
+; CHECK-NEXT:    sqrt.rn.ftz.f32 %r2, %r1;
+; CHECK-NEXT:    ld.param.b32 %r3, [sqrt_div_ftz_param_1];
+; CHECK-NEXT:    div.rn.ftz.f32 %r4, %r2, %r3;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r4;
+; CHECK-NEXT:    ret;
   %t1 = tail call float @llvm.sqrt.f32(float %a)
   %t2 = fdiv float %t1, %b
   ret float %t2
 }
 
-; CHECK-LABEL: sqrt_div_fast_ftz(
-; CHECK: sqrt.rn.ftz.f32
-; CHECK: div.approx.ftz.f32
 define float @sqrt_div_fast_ftz(float %a, float %b) #0 #1 {
+; CHECK-LABEL: sqrt_div_fast_ftz(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<5>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [sqrt_div_fast_ftz_param_0];
+; CHECK-NEXT:    sqrt.approx.ftz.f32 %r2, %r1;
+; CHECK-NEXT:    ld.param.b32 %r3, [sqrt_div_fast_ftz_param_1];
+; CHECK-NEXT:    div.approx.ftz.f32 %r4, %r2, %r3;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r4;
+; CHECK-NEXT:    ret;
   %t1 = tail call float @llvm.sqrt.f32(float %a)
   %t2 = fdiv float %t1, %b
   ret float %t2
 }
 
-; CHECK-LABEL: sqrt_div_fast_ftz_ninf(
-; CHECK: sqrt.approx.ftz.f32
-; CHECK: div.approx.ftz.f32
 define float @sqrt_div_fast_ftz_ninf(float %a, float %b) #0 #1 {
+; CHECK-LABEL: sqrt_div_fast_ftz_ninf(
+; CHECK:       {
+; CHECK-NEXT:    .reg .pred %p<2>;
+; CHECK-NEXT:    .reg .b32 %r<6>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [sqrt_div_fast_ftz_ninf_param_0];
+; CHECK-NEXT:    setp.eq.ftz.f32 %p1, %r1, 0f00000000;
+; CHECK-NEXT:    sqrt.approx.ftz.f32 %r2, %r1;
+; CHECK-NEXT:    selp.f32 %r3, 0f00000000, %r2, %p1;
+; CHECK-NEXT:    ld.param.b32 %r4, [sqrt_div_fast_ftz_ninf_param_1];
+; CHECK-NEXT:    div.approx.ftz.f32 %r5, %r3, %r4;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r5;
+; CHECK-NEXT:    ret;
   %t1 = tail call ninf afn float @llvm.sqrt.f32(float %a)
   %t2 = fdiv float %t1, %b
   ret float %t2
@@ -61,69 +117,117 @@ define float @sqrt_div_fast_ftz_ninf(float %a, float %b) #0 #1 {
 ; There are no fast-math or ftz versions of sqrt and div for f64.  We use
 ; reciprocal(rsqrt(x)) for sqrt(x), and emit a vanilla divide.
 
-; CHECK-LABEL: sqrt_div_fast_ftz_f64(
-; CHECK: sqrt.rn.f64
-; CHECK: div.rn.f64
 define double @sqrt_div_fast_ftz_f64(double %a, double %b) #0 #1 {
+; CHECK-LABEL: sqrt_div_fast_ftz_f64(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b64 %rd<5>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b64 %rd1, [sqrt_div_fast_ftz_f64_param_0];
+; CHECK-NEXT:    sqrt.rn.f64 %rd2, %rd1;
+; CHECK-NEXT:    ld.param.b64 %rd3, [sqrt_div_fast_ftz_f64_param_1];
+; CHECK-NEXT:    div.rn.f64 %rd4, %rd2, %rd3;
+; CHECK-NEXT:    st.param.b64 [func_retval0], %rd4;
+; CHECK-NEXT:    ret;
   %t1 = tail call double @llvm.sqrt.f64(double %a)
   %t2 = fdiv double %t1, %b
   ret double %t2
 }
 
-; CHECK-LABEL: sqrt_div_fast_ftz_f64_ninf(
-; CHECK: rsqrt.approx.f64
-; CHECK: rcp.approx.ftz.f64
-; CHECK: div.rn.f64
 define double @sqrt_div_fast_ftz_f64_ninf(double %a, double %b) #0 #1 {
+; CHECK-LABEL: sqrt_div_fast_ftz_f64_ninf(
+; CHECK:       {
+; CHECK-NEXT:    .reg .pred %p<2>;
+; CHECK-NEXT:    .reg .b64 %rd<8>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b64 %rd1, [sqrt_div_fast_ftz_f64_ninf_param_0];
+; CHECK-NEXT:    abs.f64 %rd2, %rd1;
+; CHECK-NEXT:    setp.lt.f64 %p1, %rd2, 0d0010000000000000;
+; CHECK-NEXT:    rsqrt.approx.f64 %rd3, %rd1;
+; CHECK-NEXT:    rcp.approx.ftz.f64 %rd4, %rd3;
+; CHECK-NEXT:    selp.f64 %rd5, 0d0000000000000000, %rd4, %p1;
+; CHECK-NEXT:    ld.param.b64 %rd6, [sqrt_div_fast_ftz_f64_ninf_param_1];
+; CHECK-NEXT:    div.rn.f64 %rd7, %rd5, %rd6;
+; CHECK-NEXT:    st.param.b64 [func_retval0], %rd7;
+; CHECK-NEXT:    ret;
   %t1 = tail call ninf afn double @llvm.sqrt.f64(double %a)
   %t2 = fdiv double %t1, %b
   ret double %t2
 }
 
-; CHECK-LABEL: rsqrt(
-; CHECK-NOT: rsqrt.approx
-; CHECK: sqrt.rn.f32
-; CHECK-NOT: rsqrt.approx
 define float @rsqrt(float %a) {
+; CHECK-LABEL: rsqrt(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<4>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [rsqrt_param_0];
+; CHECK-NEXT:    sqrt.rn.f32 %r2, %r1;
+; CHECK-NEXT:    rcp.rn.f32 %r3, %r2;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r3;
+; CHECK-NEXT:    ret;
   %b = tail call float @llvm.sqrt.f32(float %a)
   %ret = fdiv float 1.0, %b
   ret float %ret
 }
 
-; CHECK-LABEL: rsqrt_fast(
-; CHECK-NOT: div.
-; CHECK-NOT: sqrt.
-; CHECK: rsqrt.approx.f32
-; CHECK-NOT: div.
-; CHECK-NOT: sqrt.
 define float @rsqrt_fast(float %a) #0 {
+; CHECK-LABEL: rsqrt_fast(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<3>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [rsqrt_fast_param_0];
+; CHECK-NEXT:    rsqrt.approx.f32 %r2, %r1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r2;
+; CHECK-NEXT:    ret;
   %b = tail call float @llvm.sqrt.f32(float %a)
   %ret = fdiv float 1.0, %b
   ret float %ret
 }
 
-; CHECK-LABEL: rsqrt_fast_ftz(
-; CHECK-NOT: div.
-; CHECK-NOT: sqrt.
-; CHECK: rsqrt.approx.ftz.f32
-; CHECK-NOT: div.
-; CHECK-NOT: sqrt.
 define float @rsqrt_fast_ftz(float %a) #0 #1 {
+; CHECK-LABEL: rsqrt_fast_ftz(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<3>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [rsqrt_fast_ftz_param_0];
+; CHECK-NEXT:    rsqrt.approx.ftz.f32 %r2, %r1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r2;
+; CHECK-NEXT:    ret;
   %b = tail call float @llvm.sqrt.f32(float %a)
   %ret = fdiv float 1.0, %b
   ret float %ret
 }
 
-; CHECK-LABEL: fadd
-; CHECK: add.rn.f32
 define float @fadd(float %a, float %b) {
+; CHECK-LABEL: fadd(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<4>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [fadd_param_0];
+; CHECK-NEXT:    ld.param.b32 %r2, [fadd_param_1];
+; CHECK-NEXT:    add.rn.f32 %r3, %r1, %r2;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r3;
+; CHECK-NEXT:    ret;
   %t1 = fadd float %a, %b
   ret float %t1
 }
 
-; CHECK-LABEL: fadd_ftz
-; CHECK: add.rn.ftz.f32
 define float @fadd_ftz(float %a, float %b) #1 {
+; CHECK-LABEL: fadd_ftz(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<4>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [fadd_ftz_param_0];
+; CHECK-NEXT:    ld.param.b32 %r2, [fadd_ftz_param_1];
+; CHECK-NEXT:    add.rn.ftz.f32 %r3, %r1, %r2;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r3;
+; CHECK-NEXT:    ret;
   %t1 = fadd float %a, %b
   ret float %t1
 }
@@ -131,41 +235,83 @@ define float @fadd_ftz(float %a, float %b) #1 {
 declare float @llvm.sin.f32(float)
 declare float @llvm.cos.f32(float)
 
-; CHECK-LABEL: fsin_approx_afn
-; CHECK:       sin.approx.f32
 define float @fsin_approx_afn(float %a) {
+; CHECK-LABEL: fsin_approx_afn(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<3>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [fsin_approx_afn_param_0];
+; CHECK-NEXT:    sin.approx.f32 %r2, %r1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r2;
+; CHECK-NEXT:    ret;
   %r = tail call afn float @llvm.sin.f32(float %a)
   ret float %r
 }
 
-; CHECK-LABEL: fcos_approx_afn
-; CHECK:       cos.approx.f32
 define float @fcos_approx_afn(float %a) {
+; CHECK-LABEL: fcos_approx_afn(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<3>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [fcos_approx_afn_param_0];
+; CHECK-NEXT:    cos.approx.f32 %r2, %r1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r2;
+; CHECK-NEXT:    ret;
   %r = tail call afn float @llvm.cos.f32(float %a)
   ret float %r
 }
 
-; CHECK-LABEL: fsin_approx
-; CHECK:       sin.approx.f32
 define float @fsin_approx(float %a) #0 {
+; CHECK-LABEL: fsin_approx(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<3>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [fsin_approx_param_0];
+; CHECK-NEXT:    sin.approx.f32 %r2, %r1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r2;
+; CHECK-NEXT:    ret;
   %r = tail call float @llvm.sin.f32(float %a)
   ret float %r
 }
 
-; CHECK-LABEL: fcos_approx
-; CHECK:       cos.approx.f32
 define float @fcos_approx(float %a) #0 {
+; CHECK-LABEL: fcos_approx(
+; CHECK:       {
+; CHECK-NEXT:    .reg .b32 %r<3>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b32 %r1, [fcos_approx_param_0];
+; CHECK-NEXT:    cos.approx.f32 %r2, %r1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r2;
+; CHECK-NEXT:    ret;
   %r = tail call float @llvm.cos.f32(float %a)
   ret float %r
 }
 
-; CHECK-LABEL: repeated_div_recip_allowed
 define float @repeated_div_recip_allowed(i1 %pred, float %a, float %b, float %divisor) {
-; CHECK: rcp.rn.f32
-; CHECK: mul.rn.f32
-; CHECK: mul.rn.f32
-; CHECK: mul.rn.f32
-; CHECK: selp.f32
+; CHECK-LABEL: repeated_div_recip_allowed(
+; CHECK:       {
+; CHECK-NEXT:    .reg .pred %p<2>;
+; CHECK-NEXT:    .reg .b16 %rs<3>;
+; CHECK-NEXT:    .reg .b32 %r<9>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b8 %rs1, [repeated_div_recip_allowed_param_0];
+; CHECK-NEXT:    and.b16 %rs2, %rs1, 1;
+; CHECK-NEXT:    setp.ne.b16 %p1, %rs2, 0;
+; CHECK-NEXT:    ld.param.b32 %r1, [repeated_div_recip_allowed_param_1];
+; CHECK-NEXT:    ld.param.b32 %r2, [repeated_div_recip_allowed_param_3];
+; CHECK-NEXT:    rcp.rn.f32 %r3, %r2;
+; CHECK-NEXT:    mul.rn.f32 %r4, %r1, %r3;
+; CHECK-NEXT:    ld.param.b32 %r5, [repeated_div_recip_allowed_param_2];
+; CHECK-NEXT:    mul.rn.f32 %r6, %r5, %r3;
+; CHECK-NEXT:    mul.rn.f32 %r7, %r4, %r6;
+; CHECK-NEXT:    selp.f32 %r8, %r7, %r6, %p1;
+; CHECK-NEXT:    st.param.b32 [func_retval0], %r8;
+; CHECK-NEXT:    ret;
   %x = fdiv arcp float %a, %divisor
   %y = fdiv arcp float %b, %divisor
   %z = fmul float %x, %y
@@ -173,23 +319,51 @@ define float @repeated_div_recip_allowed(i1 %pred, float %a, float %b, float %di
   ret float %w
 }
 
-; CHECK-LABEL: repeated_div_recip_allowed_sel
 define float @repeated_div_recip_allowed_sel(i1 %pred, float %a, float %b, float %divisor) {
-; CHECK: selp.f32
-; CHECK: div.rn.f32
+; CHECK-LABEL: repeated_div_recip_allowed_sel(
+; CHECK:       {
+; CHECK-NEXT:    .reg .pred %p<2>;
+; CHECK-NEXT:    .reg .b16 %rs<3>;
+; CHECK-NEXT:    .reg .b32 %r<6>;
+; CHECK-EMPTY:
+; CHECK-NEXT:  // %bb.0:
+; CHECK-NEXT:    ld.param.b8 %rs1, [repeated_div_recip_allowed_sel_param_0];
+; CHECK-NEXT:    and.b...
[truncated]

``````````

</details>


https://github.com/llvm/llvm-project/pull/143776


More information about the llvm-commits mailing list