[gcc r13-3637] amdgcn: Fix instruction generation for exp2 and log2 operations

[gcc r13-3637] amdgcn: Fix instruction generation for exp2 and log2 operations

[Kwok Yeung]

https://gcc.gnu.org/g:db6a9fe39ab08526b920af2b233b06860d286943

commit r13-3637-gdb6a9fe39ab08526b920af2b233b06860d286943
Author: Kwok Cheung Yeung <kcy@codesourcery.com>
Date:   Thu Nov 3 17:19:11 2022 +0000

    amdgcn: Fix instruction generation for exp2 and log2 operations
    
    The GCN instructions for the exp2 and log2 operations are v_exp_* and v_log_*
    respectively, which unfortunately do not line up with the RTL naming
    convention.  To deal with this, a new set of int attributes is now used when
    generating the assembly for these instructions.
    
    2022-11-03  Kwok Cheung Yeung  <kcy@codesourcery.com>
    
            gcc/
            * config/gcn/gcn-valu.md (math_unop_insn): New attribute.
            (<math_unop><mode>2, <math_unop><mode>2<exec>, <math_unop><mode>2,
            <math_unop><mode>2<exec>, *<math_unop><mode>2_insn,
            *<math_unop><mode>2<exec>_insn): Use math_unop_insn to generate
            assembler output.
    
            gcc/testsuite/
            * gcc.target/gcn/unsafe-math-1.c: New.

Diff:
---
 gcc/config/gcn/gcn-valu.md                   | 20 ++++++++++++++------
 gcc/testsuite/gcc.target/gcn/unsafe-math-1.c | 10 ++++++++++
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/gcc/config/gcn/gcn-valu.md b/gcc/config/gcn/gcn-valu.md
index 3b619512e13..9f4353831bd 100644
--- a/gcc/config/gcn/gcn-valu.md
+++ b/gcc/config/gcn/gcn-valu.md
@@ -2549,13 +2549,21 @@
    (UNSPEC_SIN "sin")
    (UNSPEC_COS "cos")])
 
+(define_int_attr math_unop_insn
+  [(UNSPEC_FLOOR "floor")
+   (UNSPEC_CEIL "ceil")
+   (UNSPEC_EXP2 "exp")
+   (UNSPEC_LOG2 "log")
+   (UNSPEC_SIN "sin")
+   (UNSPEC_COS "cos")])
+
 (define_insn "<math_unop><mode>2"
   [(set (match_operand:FP 0 "register_operand"  "=  v")
 	(unspec:FP
 	  [(match_operand:FP 1 "gcn_alu_operand" "vSvB")]
 	  MATH_UNOP_1OR2REG))]
   ""
-  "v_<math_unop>%i0\t%0, %1"
+  "v_<math_unop_insn>%i0\t%0, %1"
   [(set_attr "type" "vop1")
    (set_attr "length" "8")])
 
@@ -2565,7 +2573,7 @@
 	  [(match_operand:V_FP 1 "gcn_alu_operand" "vSvB")]
 	  MATH_UNOP_1OR2REG))]
   ""
-  "v_<math_unop>%i0\t%0, %1"
+  "v_<math_unop_insn>%i0\t%0, %1"
   [(set_attr "type" "vop1")
    (set_attr "length" "8")])
 
@@ -2575,7 +2583,7 @@
 	  [(match_operand:FP_1REG 1 "gcn_alu_operand" "vSvB")]
 	  MATH_UNOP_1REG))]
   "flag_unsafe_math_optimizations"
-  "v_<math_unop>%i0\t%0, %1"
+  "v_<math_unop_insn>%i0\t%0, %1"
   [(set_attr "type" "vop1")
    (set_attr "length" "8")])
 
@@ -2585,7 +2593,7 @@
 	  [(match_operand:V_FP_1REG 1 "gcn_alu_operand" "vSvB")]
 	  MATH_UNOP_1REG))]
   "flag_unsafe_math_optimizations"
-  "v_<math_unop>%i0\t%0, %1"
+  "v_<math_unop_insn>%i0\t%0, %1"
   [(set_attr "type" "vop1")
    (set_attr "length" "8")])
 
@@ -2595,7 +2603,7 @@
 	  [(match_operand:FP_1REG 1 "gcn_alu_operand" "vSvB")]
 	  MATH_UNOP_TRIG))]
   "flag_unsafe_math_optimizations"
-  "v_<math_unop>%i0\t%0, %1"
+  "v_<math_unop_insn>%i0\t%0, %1"
   [(set_attr "type" "vop1")
    (set_attr "length" "8")])
 
@@ -2605,7 +2613,7 @@
 	  [(match_operand:V_FP_1REG 1 "gcn_alu_operand" "vSvB")]
 	  MATH_UNOP_TRIG))]
   "flag_unsafe_math_optimizations"
-  "v_<math_unop>%i0\t%0, %1"
+  "v_<math_unop_insn>%i0\t%0, %1"
   [(set_attr "type" "vop1")
    (set_attr "length" "8")])
 
diff --git a/gcc/testsuite/gcc.target/gcn/unsafe-math-1.c b/gcc/testsuite/gcc.target/gcn/unsafe-math-1.c
new file mode 100644
index 00000000000..2b54fa232e9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/gcn/unsafe-math-1.c
@@ -0,0 +1,10 @@
+/* { dg-do link } */
+/* { dg-options "-O0 -ffast-math" } */
+
+int main (void)
+{
+  float x = 0.123456f;
+
+  float r1 = __builtin_exp2f (x);
+  float r2 = __builtin_log2f (x);
+}